Two strengths of rivastigmine transdermal patch were listed on the Pharmaceutical Benefits Scheme (PBS) on 1 July 2008; a 9 mg patch (Exelon Patch 5 — used to initiate treatment) and an 18 mg patch (Exelon Patch 10). The Pharmaceutical Benefits Advisory Committee (PBAC) agreed that the patches had a similar effectiveness to the rivastigmine capsules already available on the PBS.1

The efficacy of the rivastigmine 18 mg patch (Exelon Patch 10) applied daily was shown to be similar to that of rivastigmine 6 mg capsules twice daily in a 6-month, double blinded, randomised controlled trial (n = 1195) among patients with mild to moderate Alzheimer’s disease.2,3 Both the patch and the capsules improved cognition according to the ADAS-cog score, with a difference of 1.6 points compared with placebo. A 4-point difference is commonly accepted as being clinically detectable on this scale; this was recorded in 27.4% of patients using the patch compared with 19.9% of those taking placebo (p < 0.05).2

The incidence of adverse events among people using the patch was significantly better than among people taking the capsules. Nausea was reported in 7.2% of those using the patch and 23.1% of those taking the capsules. Similarly, vomiting was reported by 6.2% and 17.0% of participants, respectively. Local skin tolerability of the patches was reported to be good, with 2.4% of patients discontinuing the patch because of skin irritation.2,3

Initiate treatment or switch a patient from oral to transdermal rivastigmine as shown in the table below.

Instructions for initiating or switching to rivastigmine patches4

Not currently using oral rivastigmine Start 9 mg patch (Exelon Patch 5)
After 4 weeks start 18 mg patch (Exelon Patch 10)
Oral rivastigmine 3–6 mg daily Switch to 9 mg patch (Exelon Patch 5).
After 4 weeks start 18 mg patch (Exelon Patch 10)
Oral rivastigmine 9–12 mg dail Switch to 18 mg patch (Exelon Patch 10)

Apply patches daily to clean, dry and hairless skin on the upper or lower back, upper arm or chest, in a place which will not be rubbed by tight clothing. The patch should not be applied to skin that is red, irritated or cut. Avoid applying the patch to the same site for 14 days.4

Only one rivastigmine patch should be worn at a time.4 Advise patients and carers that the old patch should be removed before applying the new patch, as it continues to deliver rivastigmine after 24 hours.